Studies show that married people share a lot of similar personality traits. But is that because their personalities blend over time or did they have similar personality traits at the start? A new study shows, convincingly, that people tend to choose their future spouse based on similar personalities. Indeed, marriage does not mean people become more like their spouses.
Researchers at Michigan State University analyzed data from 1,296 married couples, one of the largest studies of its kind. The couples were married an average of 19.8 years. The couples took personality assessment tests to measure whether similarities in their personalities increased with the length of the marriage.
The study showed that couples did not become more alike over time. The one personality trait that proved to be an exception to this overall conclusion was aggression. When one spouse was aggressive, the other spouse tended to develop more aggressive tendencies over time. "It is possible that individuals might reinforce each other's aggressive tendencies due to hostile interpersonal exchanges," the authors wrote. The study is published in the journal Personality and Individual Differences.
The research is important because it suggests that people with similar personalities find each other (which gives credence to matchmaking services) and, because of the shared personality traits, it's likely their offspring will be similar too.